This specification relates to mapping cognitive to functional ability, such as can be done based on results of a cognitive test and on results of a functional test that have been administered to multiple patients.
An example of a cognitive ability is episodic recall. For instance, episodic recall can be tested using a questionnaire about an individual's ability to do memory related tasks, such as remembering details of a recent conversation, remembering recent events, remembering when to take medications, and remembering to go to some future appointment. Results of this cognitive test include a subject's responses to the questionnaire—and represent subjective data. Episodic recall also can be tested using a memory task in which the subject is asked to learn a list of items, then, after several minutes delay or longer, to recall them with or without cues. Results of the latter cognitive test include a subject's responses to the memory task—and represent objective data.
An example of a measure of a functional ability is a questionnaire that asks how a range of tasks are performed—from an individual's most complex ones, to extremely simple tasks, such as walking, bathing, toileting, continence, truncal control, ability to smile, swallow, and hold up one's head. Such a measure of functional ability will be referred to, interchangeably, as a functional severity measure. Such functional ability tests can classify patients in categories corresponding into discrete values of the functional severity measure. Examples of such discrete functional severity measures include the Clinical Dementia Rating Scale, The Alzheimer's Disease Cooperative Study Activities of Daily Living Scale, and the Functional Assessment Staging Test (FAST) Procedure.
Typically, cognitive and functional abilities have been related to one another by computing their correlations. Such correlations indicate if a change in cognition is associated with a change in function or vice versa.